package cn.orange.ch10_dynamicprogramming;

/**
 * LC718.最长重复子数组
 */
public class LC718 {
    public int findLength(int[] nums1, int[] nums2) {
        int m = nums1.length;
        int n = nums2.length;
        //dp[i][j]:nums1中[0, i-1]和nums2中[0, j-1]的最长重复子数组为dp[i][j]
        int[][] dp = new int[m + 1][n + 1];
        int max = 0;
        for (int i = 1; i <= m; i++) { //dp[0][j]和dp[i][0]初始值均为1
            for (int j = 1; j <= n; j++) {
                if (nums1[i - 1] == nums2[j - 1]) {
                    dp[i][j] = 1 + dp[i - 1][j - 1];
                }
                max = Math.max(max, dp[i][j]);
            }
        }
        return max;
    }

    public static void main(String[] args) {
        LC718 alg = new LC718();
        System.out.println(alg.findLength(new int[]{1, 2, 3, 2, 1}, new int[]{3, 2, 1, 4, 7}));
    }
}
